How do you print Odd Even using Thread ?

Problem Statement: How will print Odd Even using Thread?

OR

How will you print t1 & t2 alternatively using thread?

1. import java.util.concurrent.atomic.AtomicLong;
2. class Even extends Thread {
3. AtomicLong num;
4. Object lock;
5. Even(AtomicLong num, Object lock) { // constructor
6. this.num = num;
7. this.lock = lock;
8. }
9. public void run() {
10. synchronized (lock) {
11. while (true) { // infinite loop
12. if (num.get() % 2 != 0) {
13. try {
14. lock.wait();
15. } catch (InterruptedException e) {
16. e.printStackTrace();
17. }
18. } else {
19. System.out.println("even: " + num);
20. try {
21. Thread.sleep(1000);
22. } catch (InterruptedException e) {
23. e.printStackTrace();
24. }
25. num.incrementAndGet();
26. lock.notifyAll();
27. }
28. }
29. }
30. }
31. } // end of Even class
32. 
    
33. class Odd extends Thread {
34. AtomicLong num;
35. Object lock;
36. Odd(AtomicLong num, Object lock) { // constructor
37. this.num = num;
38. this.lock = lock;
39. }
40. public void run() {
41. synchronized (lock) {
42. while (true) { // infinite loop
43. if (num.get() % 2 == 0) {
44. try {
45. lock.wait();
46. } catch (InterruptedException e) {
47. e.printStackTrace();
48. }
49. } else {
50. System.out.println("odd: " + num);
51. try {
52. Thread.sleep(1000);
53. } catch (InterruptedException e) {
54. e.printStackTrace();
55. }
56. num.incrementAndGet();
57. lock.notifyAll();
58. }
59. }
60. }
61. }
62. } // end of Odd class
63. 
    
64. public class EvenOddByThread {
65. public static void main(String[] args) {
66. AtomicLong num = new AtomicLong(1);
67. Object lock = new Object();
68. Odd odd = new Odd(num, lock);
69. Even even = new Even(num, lock);
70. even.start();
71. odd.start();
72. }
73. } // end of EvenOddByThread class

Note: To print t1 & t2 alernatively, just replace the S.O.P. stmt with t1 & t2

Output: 

odd: 1

even: 2

odd: 3

even: 4

odd: 5

even: 6

odd: 7

even: 8

odd: 9

even: 10